I still can not figure this out. It works fine for email sent to limitedwebgroup.com, but emails send to anyone else it does not work. I placed in bold what I think it causing it...but people were using the nobody@server1.limitedwebgroup.com to spam people, so I enable it. How can I modify my code to send email using a different user?

If I were to add a SPF entry in my DNS would that allow me to uncheck this setting?

we have a php script which sends the user a copy of the information they enter into a form. if the user is on our server - they get their copy (we always get a copy as we are on our server). if their email is anywhere else - the email disappears.